2.7 Gammons and Backgammons

At the end of the game, if the losing player has borne off at least
one checker, he loses only the value showing on the double cube (one
point, if there have been no doubles). However, if the loser has
not borne off any of his checkers, he is gammoned
and loses twice the value of the double cube. Or,
worse, if the loser has not borne off any of his checkers and still has
a checker on the bar or in the winner's home board, he is backgammoned
and loses three times the value of the double
cube.